Deluxe accouterments

Houston
— Home builders these days talk in terms of affordable housing. But when it came to their recent annual trade show and convention here, the theme was luxury - pure, unadulterated luxury.

As usual, kitchens and bathrooms, the two rooms that marketing experts say account for a majority of home sales, received the greatest attention.

One of the biggest attention-getters in the kitchen was Admiral Home Appliances' new Refrigerator a la Mode, which makes ice cream, frozen yogurt, cold soups and beverages, and just about any other chilled or frozen food inside its freezer compartment.

Using a patented stir-freezing technology, the new model makes the food in a self-contained, automatic device that fits into its freezer compartment. With only four moving parts, the unit can make a quart of ice cream in half an hour. The cost runs about $100 more than that of the company's standard models.

Moen has an answer to the problem of cleaning those extra-large pots and pans in the standard-size kitchen sink: an adjustable faucet that can be extended 8 inches above the drainboard. Moen's Riser, which is washerless, is available now for kitchens and will be available for lavatory sinks in late summer. To go along with it, the company also offers Swing and Spray, a hose dispenser for both soap and hand cream.

Elsewhere in the kitchen, other manufacturers simply offer new colors in their attempt to catch builders' eyes. Platinum and toast, for example, are the latest color creations of Whirlpool and Kenmore.

In the bathroom, makers also offer dazzling new shades. Kohler, for one, has added navy, taupe, and raspberry puree to its spectrum.

In recent years Kohler introduced the Environment and Habitat Masterbaths, units that offer bathers a sauna, steam, whirlpool, shower, sunlamps, and air drying, all at the touch of a button.

This year Water Jet went other manufacturers one better with its BathWomb, which it claims is ''the world's most technically advanced whirlpool bath.'' Looking somewhat like the cockpit of a jumbo jet, including the windshield, the BathWomb has a comfort-control panel, with 16 functions, allowing the bather to remain fully immersed and undisturbed while controlling the built-in stereo, answering the telephone, checking the time and water temperature, or cooling off with a jet of cool facial mist or air. The tub also has a message unit built into its integral headrest. While it has not been priced yet, it is expected to be in the $5,000-$10,000 range, a spokesman says, ''somewhat lower'' than Kohler's $10,000-$15,000 Masterbath units.

For a little less money and far more practicality, a homeowner or buyer can convert a standard bathtub into a whirlpool bath with one of Palmer Industries' new Aqua Jet baths. These four-jet units fit all standard tub spaces, have front-access panels for easy maintenance, and are said to be easy to install. They are priced from $595, about $300 more than standard tubs and faucets.

Along the same line but somewhat more expensive, Amerec's Steamer and ThermaSol's Spa can convert existing tub and shower enclosures into steam rooms. Both makers say their units are easy to install and operate.

With the Steamer, however, the enclosed area must be waterproofed; otherwise the steam will eventually destroy walls and tile. The Spa, on the other hand, comes in three sections that fit together as a completely enclosed, sealed unit, so no further waterproofing is required. Prices range from $3,400 to $4,500.

Meanwhile, the Soft Bathtub Company exhibited just the thing for builders who find it harder to ignore the bathtub - a cushioned tub.

This Seattle company's patented units are built with a resin transfer-molded fiber glass lined with inch-thick foam. They weigh only half as much as cast-iron tubs, are durable and puncture-resistant, resist scratching and marring, and won't chip. And since the cushioning acts as insulation, the water stays hot longer. The units come in more than 40 standard colors. Their cost, according to a salesman, is ''in line with high-end cast-iron tubs.''

Among other new products for the house:

* Majestic's Accent insert units turn an ordinary fireplace into an efficient home heating system that will burn safely all night. Three models, fitting almost any existing masonry fireplace, seal the opening and control both combustion air and air for home heating. Hence, the company claims, almost no heated air can escape up the chimney.

The units direct air to the wood and regulate the start-up and combustion rate of the fire. A second draft control helps burn the flue gases, improving heating efficiency, and a convection air chamber warms air that moves out into the room.

* Patio Range II, an innovative outdoor gas grill by Arkla, is said to be the first to cook and bake at the same time.

Instead of the traditional left and right burner configuration, the unit permits cooking on the front and rear. You can barbecue meats on the front of the grill while you bake a cake or warm a casserole on the back burner.

* Passive solar greenhouses and solariums, billed as ''the home addition of the '80s'' by one manufacturer, were given a step-up by English Greenhouse, which exhibited a two-story unit that can be built as high as 28 feet.